1. Field of the Invention
This invention relates to a backlight module and a panel display device using the backlight module; more particularly, this invention relates to a design that can reduce the overall size of the backlight module and the panel display device using the same.
2. Description of the Prior Art
Due to the thinness, lightness, portability of liquid crystal display (LCD) panels, and low radiation comparing to cathode ray tube (CRT) displays, the demand for LCDs has increased rapidly in recent years. Especially, the backlight module is one of the essential components of the liquid crystal display. With the improvement of the liquid crystal display technology, the backlight module is further developed for marketing purposes, such as thinness, high brightness, and low cost. In order to maintain the competitiveness of liquid crystal displays in the market, how to develop and design better backlight modules has become an important issue.
FIG. 1 schematically illustrates a conventional liquid crystal display device. As shown in FIG. 1, the liquid crystal display device includes a backlight module, a liquid crystal display panel 70, and a front frame 90 disposed on the backlight module. The backlight module includes a back plate 20, a plastic frame 30, a light source module 10, a reflector sheet 50, and an optical film 40. The back plate 20 is disposed at the bottom of the backlight module and the plastic frame 30 is disposed on the back plate 20 for fixing the light source module 10 and the optical film 40. The reflector sheet 50 is disposed at the bottom of the light source module 10 for reflecting the light leaking out from the bottom of the light source module 10. The light source modules 10 commonly used are light emitting diode (LED) light sources or lamp tube light sources. However, due to the tendency of miniaturization, smaller backlight modules usually use LEDs as the light sources and cooperate with a light guide plate to serve as an edge type backlight source. The optical film 40 includes a diffuser, a brightness enhancement film, or other films capable of adjusting the light from the light source module 10 to achieve the above design requirements.
In this design, the plastic frame 30 is designed to completely surround the light source module 10 to fix the light source module 10 and reflects leakage light from the lateral side. Moreover, the plastic frame 30 can also extend between the liquid crystal display panel 70 and the front frame 90 to avoid possible short circuit caused by the contact between the liquid crystal display 70 and the front frame 90. However, in the conventional design, because the thickness of the plastic frame 30 can not be reduced, the overall size of the display device is increased, resulting in the failure of meeting the miniaturization requirement.